Universal Containers manages leads in a Lead qualification queue where sales reps can accept ownership of the Lead. Campaign members are required to…

This validation rule is designed to fire only when a new Lead record is created (ISNEW()) and its owner is a Queue. The function ISBLANK(Owner:User.Id) is a standard method to determine if the polymorphic Owner field points to a Queue. If the owner were a User, Owner:User.Id would contain a value and ISBLANK would be false. By combining these conditions with AND, the rule prevents a new Lead from being assigned directly to a queue. This enforces a business process where a Lead must first be assigned to a specific user, who can then be added to a campaign, before it is potentially reassigned to a qualification queue.

A. The OwnerId field on a Lead is a required system field and can never be blank. Therefore, this validation rule would never be triggered.

B. This rule would fire for all existing records (NOT(ISNEW()) is true for them), preventing users from making any updates, which is incorrect functionality.

D. This rule, NOT(ISBLANK(Lead.Owner:Queue.Id)), evaluates to true whenever the owner is a queue. It would prevent any Lead, new or existing, from being queue-owned, which contradicts the stated business process.

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1. Trailhead, Salesforce Platform Basics, "Validation Rules" Module: This module explains that validation rules verify that the data a user enters in a record meets the standards you specify before the user can save the record. The formula must evaluate to "True" for the error message to display. This supports the basic structure of the chosen answer.

2. Salesforce Help, Formula Operators and Functions, "ISNEW()": "Checks if the formula is running during the creation of a new record and returns TRUE if it is. If an existing record is being updated, this function returns FALSE." This confirms the function of the ISNEW() part of the formula.

3. Salesforce Help, Formula Operators and Functions, "ISBLANK()": "Determines if an expression has a value and returns TRUE if it does not." When used with a polymorphic relationship field like Owner, ISBLANK(Owner:User.Id) correctly returns TRUE if the Owner is a Queue, as the specific path to a User record is blank.

4. Salesforce Help, Formula Operators and Functions, "CASE()": The documentation for the CASE() function provides an official example of accessing fields on the polymorphic Owner relationship: CASE(Owner:Queue.Type, 'Regular', 1, 'Territory', 2, 'Group', 3, 0). This officially documents the Owner:[ObjectType].[FieldName] syntax pattern used in the question's options.